A new piece of paperwork was added to our retinue of visas, port clearances, Customs declarations, bank receipts, and health certificates. It was a single sheet, double sided, and filled from top to bottom with shorthand. No stamps adorned the velum; no official would ever ask to see it. We weren't even required to get one at every port, though we would spend more anxious effort acquiring it than any other document we carried. In the most immediate sense it could be the most valuable piece of paper on board; our lives could depend upon the encryptions it contained. For this piece of cheap, flapping fax machine regurgitation was the tracking report monitoring the barometric pressure, sea state, air temperature, wind speed and presence or absence of storms for the entire western coast of Mexico. We were sailing straight out into the Gulf of Tehuantepec, the north-facing indent on the extreme southwestern edge of Mexico; the cradle and nursery for early season Pacific hurricanes � and the simple lack of two pages of weather reports from up and down the one and a half thousand mile Mexican shoreline could get us killed. Already, back while we were sailing between Belize and Roatan Island, an unheard-of May hurricane (the first in 105 years) had been spawned just south of Tehuantepec and spun its fury against the banks of southern Mexico and Guatemala. Obviously, this would be a ripe season for the spiraling fruits of summer storm season....
A few notes about hurricanes: Hurricane season typically begins about June 1st and lasts until October. Of course, nothing on our journey has been typical, weather being no exception. This year the first tropical cyclone formed in May. So it behooved us to be up to speed on how to recognize the conditions necessary to form one of these monstrosities and keep close track of the movements of anything likely to become one no matter where it was located. First off, several factors must converge for the formation of a hurricane.
1) A tropical depression must be present. Tropical depressions are the result of bands of low pressure, usually spaced three to five days apart (from a fixed point on land) moving in a westerly and/or northerly direction, that encounter a set of the conditions below.
2) Constant rain. A storm need not be raging, but there will be a cloud cover thick enough to produce precipitation.
3) Barometric pressure of 1004 milibars or lower. A rapidly falling barometer is like the shirt on the bomb squad guy: If You See Me Running, Try To Keep UP. Ideally, you want to be in a pressure range of 1009 or higher.
4) Surface temperature of 78.8 degrees Fahrenheit or more.
5) East winds not confined to near surface altitudes.
All conditions being met, a tropical depression can become a tropical storm, which may remain a tropical storm or become more powerful. Drawing energy from the evaporation of water as the sun scorches the sea, the storm can increase in strength until it assumes full fledged hurricane status. Winds reaching one hundred miles per hour are standard.
Brian outlined the plan for our avoiding these natural disasters. In order to dodge the formation of a tropical storm or hurricane, he told us, we would have to time our departures between tropical waves. T-waves are the low pressure bands that swing northwest through the eastern Pacific on the three to five day intervals. If we set out on the heals of the tropical waves they would outdistance us ahead and we'd make the next port before the oncoming wave could overtake us. Hopefully. Always keep an eye on the barometer. Always be aware of the sea state and surrounding conditions. And if we weren't making four knots or better under sail we'd go to the engine. This was not the place to spend half a day bobbing on the tracks while the locomotive picked up steam behind us. We would have to become amateur meteorologists � by the time the reports of a tropical depression would be available to us it would already have become a tropical storm (or hurricane) or it wouldn't. So we'd have to assimilate all the information and make our own predictions.
The guides give specific instructions concerning the navigation of Tehuantepec, the Sea of Death as some would style it. Firstly, NEVER attempt a crossing during hurricane season, ESPECIALLY in the midst of summer. Secondly, HUG THE COAST. Keeping "one foot on shore" adds some miles but protects you from the stiff offshore winds, Tehuantepeckers, that come roaring across the narrow Isthmus of Tehuantepec from the Gulf of Mexico. Funneled between mountain ranges the winds generated in the eastern gulf pick up speed and blast into the western gulf with a fury known to blow boats 500 miles out to sea. Also, tropical depressions tend to form miles out over the ocean and a tropical storm or hurricane will almost assuredly move west-northwest. Staying near the shoreline lessens your chances of being run over. Simply use your depthfinder to follow the ten fathom line. Thirdly, power all the way. Only attempt a crossing with a reliable engine that can take you 10 knots or better rather than risk dithering around when the wind subsides. Furthermore, never exceed the range of your fuel when picking your next port. Oh, yeah, and fourthly, for the love of god, don't try this in a little boat....
Disclaimer: By now you've probably guessed that we broke each rule outlined above. We stringently recommend that you don't follow our example. Do your cruising during winter, listen to the experienced mariners who write the guides, play it safe.
....But, if you're bound and determined, as we were, then here is how you do it and why we did:
Firstly, our timing placed us in the middle of hurricane season. We'd felt that the Caribbean presented a much greater risk to us this time of year and had scheduled accordingly. Secondly, hugging the coast was out. Our depthfinder has not worked since the second season after we installed it....twenty years ago. We felt that we'd be placing ourselves in far greater danger by staying close to shore (particularly at night) than by staying well clear of land. In addition, Tehuantepeckers are winter phenomena � we wouldn't be encountering them in July. Thirdly, our fuel range is 150 miles. That's basically half the distance from Madero to any port the other side of the gulf. Even hugging shore we would run out of fuel (making that alternative even less enticing) long before reaching a safe harbor. Our engine, trusty though it has been, takes us to a maximum of 7 knots under ideal conditions. When the wind is with us we do better under sail. Fourthly, we have Faith.
We planned every aspect of our crossing in advance based on Brian's previous studies and the gathering of all the local information at hand. Most importantly we had a weather window opening on the fifth of July � a tropical wave passed Puerto Madero on the afternoon of the fourth giving us three days until the next one would cross the same spot. That made a total of three and a half days before the following wave would pass us; safely in our next port, we hoped. We would rely on our sails as long as they would pull us at four knots or better. Whenever we dropped below the required speed we'd press on with the iron jenny. Barometer checks regularly made would help us detect an approaching depression (an unlikely event, but who can say it can't happen if it does?). In the event the barometer fell below 1006 we'd run for the nearest shore. Our aim would be to head for Huatulco, then adjust and make for Puerto Angel (pronounced An � Hayl) twenty miles further up coast if weather permitted. Reefing lines and ties would always be at the ready. Storm sheets and jib prepared for instant replacement of the big Genoa. When we left Puerto Madero we were a well prepared team. All eyes on deck scanned sky and sea, day and night. And we had one of the most beautiful three day sails of our journey.